Electric lamp



(No Model.)

G. W. BEARDSLEE.

ELECTRIC LAMP. `No. 265,737. Patented Oct. l0, 18822 Pfc; 1. f'fcL/Qf. ffc, .3

N. PETERS, Pmm-Limagnpmn wnmmgwn, n. C.

UNITED STATES PATENT OFFICE.

i GEORGE WV. BEARDSLEE, OF BROOKLYN, NEW YORK, ASSIGNOR "TO WILLIAM F. JOBBINS, OF EAST ORANGE, NEW JERSEY.

ELECTRIC LAMP.

SPECIFICATION forming part of Letters Patent No. 265,73*?, dated October` 10, 1882.

(No model.)

To all whom tt may concern:

Be it known that I, GEORGE W. BEAEDS- LEE, ol'Brooklyn, Kings county, State of New York, have invented certain Improvements in Electric Lamps, of which the following is a specification.

rThe main object of my/invention is to so construct an electric lamp as to lessen the consumption of the carbons when the lamp is in 1o operation; and this object I attain by providing the globe or inclosure for the light with a closed bottom and a contracted opening at the upper end, as more fully described hereinafter.

My invention also relates to cert-ain improvements in the detailed construction of the lamp,

as hereinafter set forth.

In the accompanying drawings, Figure l is a side view ot' an electric incandescent lamp embodying my invention; Fig. 2, a vertical 2o section of the lamp shown in Fig. 1; and Fig. 3, a View ot' an arc-light lamp embodying my invention.

Electric lamps, as usually constructed for the burning of carbon or equivalent points, are

z5 provided either with open globes, allowing a free circulation of air about the carbons, or with a closed glass case, so that the cai-bons are practically in a vacuum. In the one case the admission of a free circulation of air about 3o the carbon points induces an unnecessarilyrapid consumption of the carbons, while in thc other case there is the trouble andinconvenience attending the openingvof the air-tight inclosure whenever a change 'has to be made in 3 5 the carbons.

In my invention the globe for the carbons is closed at its lower end, and has at the upper end a contracted opening of such a character that while it will prevent a free circulation ot' 4o air about the carbons will allow expanded air to escape from the globe and permit the free passage of the carbon through said opening.

Referring to Figs. l and 2 A is a glass globe, having an enlarged spherical portion, a, in

., which the carbons are intended to burn, and

contracted tubular portions above and below, the lower end being fitted tightly into the base B of the frame, as hereinafter described.

C is acylindrical piece of carbon, which is se- 5o cured in a suitable holder, l), and in the type of lamp shown in Figs. l and 2 is preferably made thick, so as to consume slowly. This carbon passes freely through the upper tubular portion ot' the globe A, so as to leave a small space between the inner face of the tube and the carbon, and the latter is held in the proper position, so that it'will be about the center of the globe, by an adjustable stop, m, secured to the holder D and resting on the top of the tubular portion of the globe A. 6o This holder D is provided with a recess and set-screw, It, for the connection ofthe terminal wire.

Against the end of the carbon O bears the carbon pencil i, which passes through a tube, h, of carbon secured in and forming a continuation of a metal tube, g. This tube g is closed at its lower end by a plug carrying a screw,

k, for the terminal wire, and within the tube is a rod,j, supported on a spiral spring, c, which 7o keeps the pencil fi in contact with the bottom ofthe carbon O.

rThe base B may be in the form ofa cylinder,

Z1, contracted at its lower end, and within this may be iitted a tube, e, of smaller size. The space between the cylinder l) and tube c may be tilled with plaster-of-paris or other poor conductor of heat. A metal plate, f, is secured to the lower end of the base B, and in a central opening in this plate and the neck c 8o is titted the tube g. The tubular lower end of the globe tits into the tube c and may be hermetically sealed therein by any suitable sealing material, p-such as powdered asbestus, plaster-of-paris, or similar material-so that air cannot enter the lower end of the globe. The light is produced by the incandescence of the pencil t when an electric current is passed through the carbons. rlhe intense heat caused by the action ot' the electric current upon the 9o carbons will highly raret'y the air in the globe,

so that it will pass out between the carbon O and the tube; but this, the only opening, is too contracted to permit the air to enter and circu late about the carbens whilethe lamp is lighted. The result will be that the carbons will burn in an atmosphere so rarefied as to be almost a vacuum, so th at the combustion ofthe carbons will be very slow. Thus, while securing nearly all the advantages attending the use ot' a vacuum, roo

the construction described permits the ready renewal of the carbons.

In Fig. 3 I have shown my invention as applied to an are electric light. Gand C are the positive and negative carbons, the form er beingsecured in the holder D, While the carbon G is fixed in the base B. Into this base is fitted the lower end of the globe A, so as to practically prevent the entrance of air at that point, while the upper end of the globe has a contracted opening l'or the purpose described above. Through this opening passes the carbon C and its holder D, which latter is under the control of the regulating,` devices in the case l, for forming and maintaining the are.

It will be understood that the form and dimensions ofthe globe or inclosure for the ligh ting` devices may be varied without departing from my invention; and an outer globe, G, may also be employed.

l claim as my invention- 1., An electric-light lamp provided with cnrbons and carbon-holders, in combination with a globe or inclosure havingone end closed, and at the other end a contracted opening, through which one of the carbons freely passes, substantially as and for the purpose set forth.

2. The combination of the carbon C ol an,

electric lamp with a tube, la, of carbon, and a pencil, t', Within said carbon tube, as and for the purpose described.

3. The combination of the carbon points of an electric lamp and globe, A, with the carbonholder D, havinga stop, m, adjustably secured thereto, andadapted to rest on and be supported by the top of the globe, as and for the purpose specified.

Witness my hand, June 11, 1881.

GEORGE W, BEARDSLEE.

In presence of- P. B. VERMILYA, A. G. W. VERMILYA. 

